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Topic: Commercial Gouda press (Read 10261 times)

I saw a movie making Commercial Gouda.The press is done with hydraulic machine. theyput about 10 molds of cheese on one other and pressthem together. So the mold at the bottom has about 9cheese on it and the one at the top has no mold on it so the weight of the press applied on the molds has a big different. Is their a bigdifferent between the cheeses ?

I saw a movie making Commercial Gouda.The press is done with hydraulic machine. theyput about 10 molds of cheese on one other and pressthem together. So the mold at the bottom has about 9cheese on it and the one at the top has no mold on it so the weight of the press applied on the molds has a big different. Is their a bigdifferent between the cheeses ?

The only difference between the cheeses is due to gravity which I would think is negligible here given the magnitude of the pressure applied to goudas. I doubt there is much of a difference at all unless you are stacking a ton of cheeses on top of one another. The gravitational force would have to be approximately of the same order as the pressing force. I would expect it is not within an order of magnitude, maybe two. IE, you press a 2 lb gouda with about 50 or more lbs given about a 4-5 in mold, they are off by an order of magnitude or about a factor of 10. Now hypothetically, if you stacked 10 of them on top of each other and kept the pressing force at 50 lbs, you would have a total of 20 additional lbs acting on the bottom cheese. 20 is sufficiently close to the pressing force of 50 lbs for it to become significant.

I saw a press that pressed 10 or so molds at one time, but instead of being stacked vertically, they were pressed horizontally...as a result I would think there would be a relatively small difference in pressure between the middle molds and the end ones. It could possibly be significant enough to warrant a rotation.

I saw a press that pressed 10 or so molds at one time, but instead of being stacked vertically, they were pressed horizontally...as a result I would think there would be a relatively small difference in pressure between the middle molds and the end ones. It could possibly be significant enough to warrant a rotation.

Actually, in that case the difference would be zero. The force on them would be identical due to Newton's third law of physics. Kind of a weird truth.

I saw a press that pressed 10 or so molds at one time, but instead of being stacked vertically, they were pressed horizontally...as a result I would think there would be a relatively small difference in pressure between the middle molds and the end ones. It could possibly be significant enough to warrant a rotation.

Actually, in that case the difference would be zero. The force on them would be identical due to Newton's third law of physics. Kind of a weird truth.

Or if you really want to be a nerd about it. The gravitational component of the net force vector is orthogonal to the pressing (normal) force component and thus contributes nothing to the pressure on each individual mold. (Newton's third law effectively ensures the pressing force is uniform on each mold).

Actually, in that case the difference would be zero. The force on them would be identical due to Newton's third law of physics. Kind of a weird truth.

While I do understand what you said, i do believe that isn't entirely correct. There is resistance, and friction involved. The transfer of force from one to the next to the next etc would, I believe, diminish somewhat in the middle ones. However, the difference may not be enough to be of any significance.

Actually, in that case the difference would be zero. The force on them would be identical due to Newton's third law of physics. Kind of a weird truth.

While I do understand what you said, i do believe that isn't entirely correct. There is resistance, and friction involved. The transfer of force from one to the next to the next etc would, I believe, diminish somewhat in the middle ones. However, the difference may not be enough to be of any significance.

Sure, but assuming your molds are properly constructed (and thus your followers slide properly), friction should be negligible, particularly since in this case friction is a function of gravity which is very small compared with the pressing force (again, assuming your molds are not made of sandpaper).

Its all about magnitudes. The magnitude of the pressing force is so dang high compared to everything else that is demolishes any other forces which might be contributing here. Is there a friction component? Undoubtedly. But factoring it in would be a matter of splitting hairs. Physics is never about absolutes (very very rarely at least), it is all about making dang good approximations by ignoring the details which approach pointlessness (IE details that would never in a million years effect the outcome of the calculations involved).

Not friction with the follower (other than very little, since there would be some contact) but rather the contents of the mold...you are applying pressure to a material that becomes compressed. Consider a series of springs and you apply force to both ends of the series...you would see more compression at the ends than you would in the center. More than likely the difference (as in with pressing cheeses) is insignificant.

Try a mental experiment.You have 5 springs and a scale. Each spring weighs 1 lb. Stack the springs 5 high on the scale. What does the scale read?Stack the springs 4 high on the scale. What does the scale read?Now add a 1 lb weight on top of the 4 th spring. What does the scale read?Each spring is independent and does not know if it is a spring or a weight on top of it.

I think the weight of the springs problem is a subtly different issue. For one, with the molds (springs) being pressed horizontally, weight (gravity) does not play a part in the answer. On the other hand, I do see the point you are making. If you had a line of molds (horizontally) that approached infinity, and applied pressure to one end, would the other end experience any pressure at all?

Something has always got to be pushing back. If I put 10 lbs of load on one side of something, if it's in equilibrium (not moving), then something is pushing back with 10 lbs.

In a vertical cheese press system, the load carried by the bottom cheese (assuming no load is transfer to the molds--which a good design would try to ensure) would be equal to the load applied to the top cheese plus the weight of each of the cheeses and molds on top.

In a horizontal system, you can introduce a little bit of complexity in the analysis if the molds are resting on something, but if they are suspended between the load applying end (a piston of some sort, perhaps) and the "base" such that those are the only two points in contact with the stack of cheeses, each cheese will experience the same force.

So, in the case of an infinitely long, horizontal stack of molds, if the molds are only touching one another, they will each be carrying the same load. If they are resting on the ground, the friction between each mold and the ground will lessen the load the next cheese carries until there is no longer any load applied to the cheeses. Example: 10 lbs of load is applied, cheese 1 experiences 10 lbs, but 1 lb of the reaction is provided not by the next cheese in line, but by friction with the ground. Cheese 2 expereiences 9 lbs, Cheese 3 8 lbs, etc.